Robot wars is hard to resist. A bunch of engineers and fabricators of machines compete to build a robot that can kill all other robots. What’s interesting is to see the evolution of design- which is part determined by the robot arena and partly by the opposing robots.

The arena is a caged off zone- maybe the size of a squash court with a few tethered house robots that are larger than the competers but fairly predictable. They stick to their patch so it’s important not to break down within their ambit. There are various hazards- a hole that appears- which once you are in is very hard to extricate yourself from.

But the major design influence is the opposing robot.

At first the robots looked cool and robot like. This changed over time as top heavy robots proved easy to flip. So new ones became flip friendly- able to right themselves or even run when upside down. They became sleek and wedge shaped with hidden wheels – and all had wheels- none have legs which I guess would make it too hard to be an evenly matched game.

The robots defeat each other either by smashing, cutting, flipping or electrocuting the opposite machine. For a while no technology prevailed then it became apparent that a bit of each didn’t work. Your robot had to commit to one tactic or another. Hammer wielding smashers worked for a while. Then wedge powered flippers were the rage. Then a team looked at the rather feeble circular saws on some robots and built a spinning rotor- like a mower rotor- out of turbine steel. It was lethal and virtually unbreakable. Just getting the tip of your robot caught by this killer device could result in it being spun out of the arena.

Of course you need speed, manoeuvrability, armament and the ability to react to being flipped- but at the end of the day you need unstoppable firepower that is fast. A hammer or even a taser is a bit slow. A rotating blade is like a gatling gun- devastating. Momentum is what halts another object- Mass multipled by velocity. Mass is not enough. And speed is not enough. Thinking about devices that raise both of these easily (things that spin rather than oscillate, stop-start) is a good way forward.

Even when designing other products think about its momentum, think about ways of making it spin so as not to need constant inputs of energy to keep starting it again. Think of a book, instead of being launched (with the inevitable return to earth), being put in a series of low orbits that just keep rising. What a ‘low orbit’ would be or what form this spinning would take would obviously differ for each product.